modules/libjar/nsJARInputStream.cpp
author Andreea Pavel <apavel@mozilla.com>
Tue, 21 Aug 2018 20:20:24 +0300
changeset 490366 d8a7212c51a48253bfa9551ecc9318a9536c62d4
parent 425542 704c58d8803e7a0388111af34325dc1964cd4a3b
child 508163 6f3709b3878117466168c40affa7bca0b60cf75b
permissions -rw-r--r--
Backed out 6 changesets (bug 1396821) for linux tier2 build bustages on a CLOSED TREE Backed out changeset 2fa2975f97e3 (bug 1396821) Backed out changeset c5895db52483 (bug 1396821) Backed out changeset 5c0ddd45f926 (bug 1396821) Backed out changeset 7c97853a85b9 (bug 1396821) Backed out changeset b61ce753f01e (bug 1396821) Backed out changeset 7ef3912feb2c (bug 1396821)

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* nsJARInputStream.cpp
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsJARInputStream.h"
#include "zipstruct.h"         // defines ZIP compression codes
#ifdef MOZ_JAR_BROTLI
#include "brotli/decode.h"  // brotli
#endif
#include "nsZipArchive.h"

#include "nsEscape.h"
#include "nsIFile.h"
#include "nsDebug.h"
#include <algorithm>
#if defined(XP_WIN)
#include <windows.h>
#endif

/*---------------------------------------------
 *  nsISupports implementation
 *--------------------------------------------*/

NS_IMPL_ISUPPORTS(nsJARInputStream, nsIInputStream)

/*----------------------------------------------------------
 * nsJARInputStream implementation
 *--------------------------------------------------------*/

nsresult
nsJARInputStream::InitFile(nsJAR *aJar, nsZipItem *item)
{
    nsresult rv = NS_OK;
    MOZ_ASSERT(aJar, "Argument may not be null");
    MOZ_ASSERT(item, "Argument may not be null");

    // Mark it as closed, in case something fails in initialisation
    mMode = MODE_CLOSED;
    //-- prepare for the compression type
    switch (item->Compression()) {
       case STORED:
           mMode = MODE_COPY;
           break;

       case DEFLATED:
           rv = gZlibInit(&mZs);
           NS_ENSURE_SUCCESS(rv, rv);

           mMode = MODE_INFLATE;
           mInCrc = item->CRC32();
           mOutCrc = crc32(0L, Z_NULL, 0);
           break;

#ifdef MOZ_JAR_BROTLI
       case MOZ_JAR_BROTLI:
           mBrotliState = BrotliDecoderCreateInstance(nullptr, nullptr, nullptr);
           mMode = MODE_BROTLI;
           mInCrc = item->CRC32();
           mOutCrc = crc32(0L, Z_NULL, 0);
           break;
#endif

       default:
           return NS_ERROR_NOT_IMPLEMENTED;
    }

    // Must keep handle to filepointer and mmap structure as long as we need access to the mmapped data
    mFd = aJar->mZip->GetFD();
    mZs.next_in = (Bytef *)aJar->mZip->GetData(item);
    if (!mZs.next_in) {
        nsZipArchive::sFileCorruptedReason = "nsJARInputStream: !mZs.next_in";
        return NS_ERROR_FILE_CORRUPTED;
    }
    mZs.avail_in = item->Size();
    mOutSize = item->RealSize();
    mZs.total_out = 0;
    return NS_OK;
}

nsresult
nsJARInputStream::InitDirectory(nsJAR* aJar,
                                const nsACString& aJarDirSpec,
                                const char* aDir)
{
    MOZ_ASSERT(aJar, "Argument may not be null");
    MOZ_ASSERT(aDir, "Argument may not be null");

    // Mark it as closed, in case something fails in initialisation
    mMode = MODE_CLOSED;

    // Keep the zipReader for getting the actual zipItems
    mJar = aJar;
    nsZipFind *find;
    nsresult rv;
    // We can get aDir's contents as strings via FindEntries
    // with the following pattern (see nsIZipReader.findEntries docs)
    // assuming dirName is properly escaped:
    //
    //   dirName + "?*~" + dirName + "?*/?*"
    nsDependentCString dirName(aDir);
    mNameLen = dirName.Length();

    // iterate through dirName and copy it to escDirName, escaping chars
    // which are special at the "top" level of the regexp so FindEntries
    // works correctly
    nsAutoCString escDirName;
    const char* curr = dirName.BeginReading();
    const char* end  = dirName.EndReading();
    while (curr != end) {
        switch (*curr) {
            case '*':
            case '?':
            case '$':
            case '[':
            case ']':
            case '^':
            case '~':
            case '(':
            case ')':
            case '\\':
                escDirName.Append('\\');
                MOZ_FALLTHROUGH;
            default:
                escDirName.Append(*curr);
        }
        ++curr;
    }
    nsAutoCString pattern = escDirName + NS_LITERAL_CSTRING("?*~") +
                            escDirName + NS_LITERAL_CSTRING("?*/?*");
    rv = mJar->mZip->FindInit(pattern.get(), &find);
    if (NS_FAILED(rv)) return rv;

    const char *name;
    uint16_t nameLen;
    while ((rv = find->FindNext( &name, &nameLen )) == NS_OK) {
        // Must copy, to make it zero-terminated
        mArray.AppendElement(nsCString(name,nameLen));
    }
    delete find;

    if (rv != NS_ERROR_FILE_TARGET_DOES_NOT_EXIST && NS_FAILED(rv)) {
        return NS_ERROR_FAILURE;    // no error translation
    }

    // Sort it
    mArray.Sort();

    mBuffer.AssignLiteral("300: ");
    mBuffer.Append(aJarDirSpec);
    mBuffer.AppendLiteral("\n200: filename content-length last-modified file-type\n");

    // Open for reading
    mMode = MODE_DIRECTORY;
    mZs.total_out = 0;
    mArrPos = 0;
    return NS_OK;
}

NS_IMETHODIMP
nsJARInputStream::Available(uint64_t *_retval)
{
    // A lot of callers don't check the error code.
    // They just use the _retval value.
    *_retval = 0;

    switch (mMode) {
      case MODE_NOTINITED:
        break;

      case MODE_CLOSED:
        return NS_BASE_STREAM_CLOSED;

      case MODE_DIRECTORY:
        *_retval = mBuffer.Length();
        break;

      case MODE_INFLATE:
#ifdef MOZ_JAR_BROTLI
      case MODE_BROTLI:
#endif
      case MODE_COPY:
        *_retval = mOutSize - mZs.total_out;
        break;
    }

    return NS_OK;
}

NS_IMETHODIMP
nsJARInputStream::Read(char* aBuffer, uint32_t aCount, uint32_t *aBytesRead)
{
    NS_ENSURE_ARG_POINTER(aBuffer);
    NS_ENSURE_ARG_POINTER(aBytesRead);

    *aBytesRead = 0;

    nsresult rv = NS_OK;
MOZ_WIN_MEM_TRY_BEGIN
    switch (mMode) {
      case MODE_NOTINITED:
        return NS_OK;

      case MODE_CLOSED:
        return NS_BASE_STREAM_CLOSED;

      case MODE_DIRECTORY:
        return ReadDirectory(aBuffer, aCount, aBytesRead);

      case MODE_INFLATE:
#ifdef MOZ_JAR_BROTLI
      case MODE_BROTLI:
#endif
        if (mZs.total_out < mOutSize) {
          rv = ContinueInflate(aBuffer, aCount, aBytesRead);
        }
        // be aggressive about releasing the file!
        // note that sometimes, we will release  mFd before we've finished
        // deflating - this is because zlib buffers the input
        if (mZs.avail_in == 0) {
            mFd = nullptr;
        }
        break;

      case MODE_COPY:
        if (mFd) {
          uint32_t count = std::min(aCount, mOutSize - uint32_t(mZs.total_out));
          if (count) {
              memcpy(aBuffer, mZs.next_in + mZs.total_out, count);
              mZs.total_out += count;
          }
          *aBytesRead = count;
        }
        // be aggressive about releasing the file!
        // note that sometimes, we will release mFd before we've finished copying.
        if (mZs.total_out >= mOutSize) {
            mFd = nullptr;
        }
        break;
    }
MOZ_WIN_MEM_TRY_CATCH(rv = NS_ERROR_FAILURE)
    return rv;
}

NS_IMETHODIMP
nsJARInputStream::ReadSegments(nsWriteSegmentFun writer, void * closure, uint32_t count, uint32_t *_retval)
{
    // don't have a buffer to read from, so this better not be called!
    return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP
nsJARInputStream::IsNonBlocking(bool *aNonBlocking)
{
    *aNonBlocking = false;
    return NS_OK;
}

NS_IMETHODIMP
nsJARInputStream::Close()
{
    if (mMode == MODE_INFLATE) {
        inflateEnd(&mZs);
    }
#ifdef MOZ_JAR_BROTLI
    if (mMode == MODE_BROTLI) {
        BrotliDecoderDestroyInstance(mBrotliState);
    }
#endif
    mMode = MODE_CLOSED;
    mFd = nullptr;
    return NS_OK;
}

nsresult
nsJARInputStream::ContinueInflate(char* aBuffer, uint32_t aCount,
                                  uint32_t* aBytesRead)
{
    bool finished = false;

    // No need to check the args, ::Read did that, but assert them at least
    NS_ASSERTION(aBuffer,"aBuffer parameter must not be null");
    NS_ASSERTION(aBytesRead,"aBytesRead parameter must not be null");

    // Keep old total_out count
    const uint32_t oldTotalOut = mZs.total_out;

    // make sure we aren't reading too much
    mZs.avail_out = std::min(aCount, (mOutSize-oldTotalOut));
    mZs.next_out = (unsigned char*)aBuffer;

#ifndef MOZ_JAR_BROTLI
    MOZ_ASSERT(mMode == MODE_INFLATE);
#endif
    if (mMode == MODE_INFLATE) {
        // now inflate
        int zerr = inflate(&mZs, Z_SYNC_FLUSH);
        if ((zerr != Z_OK) && (zerr != Z_STREAM_END)) {
            nsZipArchive::sFileCorruptedReason = "nsJARInputStream: error while inflating";
            return NS_ERROR_FILE_CORRUPTED;
        }
        finished = (zerr == Z_STREAM_END);
#ifdef MOZ_JAR_BROTLI
    } else {
        MOZ_ASSERT(mMode == MODE_BROTLI);
        /* The brotli library wants size_t, but z_stream only contains
         * unsigned int for avail_* and unsigned long for total_*.
         * So use temporary stack values. */
        size_t avail_in = mZs.avail_in;
        size_t avail_out = mZs.avail_out;
        size_t total_out = mZs.total_out;
        BrotliDecoderResult result = BrotliDecoderDecompressStream(
            mBrotliState,
            &avail_in, const_cast<const unsigned char**>(&mZs.next_in),
            &avail_out, &mZs.next_out, &total_out);
        /* We don't need to update avail_out, it's not used outside this
         * function. */
        mZs.total_out = total_out;
        mZs.avail_in = avail_in;
        if (result == BROTLI_DECODER_RESULT_ERROR) {
            nsZipArchive::sFileCorruptedReason = "nsJARInputStream: brotli decompression error";
            return NS_ERROR_FILE_CORRUPTED;
        }
        finished = (result == BROTLI_DECODER_RESULT_SUCCESS);
#endif
    }

    *aBytesRead = (mZs.total_out - oldTotalOut);

    // Calculate the CRC on the output
    mOutCrc = crc32(mOutCrc, (unsigned char*)aBuffer, *aBytesRead);

    // be aggressive about ending the inflation
    // for some reason we don't always get Z_STREAM_END
    if (finished || mZs.total_out == mOutSize) {
        if (mMode == MODE_INFLATE) {
            inflateEnd(&mZs);
        }

        // stop returning valid data as soon as we know we have a bad CRC
        if (mOutCrc != mInCrc) {
            nsZipArchive::sFileCorruptedReason = "nsJARInputStream: crc mismatch";
            return NS_ERROR_FILE_CORRUPTED;
        }
    }

    return NS_OK;
}

nsresult
nsJARInputStream::ReadDirectory(char* aBuffer, uint32_t aCount, uint32_t *aBytesRead)
{
    // No need to check the args, ::Read did that, but assert them at least
    NS_ASSERTION(aBuffer,"aBuffer parameter must not be null");
    NS_ASSERTION(aBytesRead,"aBytesRead parameter must not be null");

    // If the buffer contains data, copy what's there up to the desired amount
    uint32_t numRead = CopyDataToBuffer(aBuffer, aCount);

    if (aCount > 0) {
        // empty the buffer and start writing directory entry lines to it
        mBuffer.Truncate();
        mCurPos = 0;
        const uint32_t arrayLen = mArray.Length();

        for ( ;aCount > mBuffer.Length(); mArrPos++) {
            // have we consumed all the directory contents?
            if (arrayLen <= mArrPos)
                break;

            const char * entryName = mArray[mArrPos].get();
            uint32_t entryNameLen = mArray[mArrPos].Length();
            nsZipItem* ze = mJar->mZip->GetItem(entryName);
            NS_ENSURE_TRUE(ze, NS_ERROR_FILE_TARGET_DOES_NOT_EXIST);

            // Last Modified Time
            PRExplodedTime tm;
            PR_ExplodeTime(ze->LastModTime(), PR_GMTParameters, &tm);
            char itemLastModTime[65];
            PR_FormatTimeUSEnglish(itemLastModTime,
                                   sizeof(itemLastModTime),
                                   " %a,%%20%d%%20%b%%20%Y%%20%H:%M:%S%%20GMT ",
                                   &tm);

            // write a 201: line to the buffer for this item
            // 200: filename content-length last-modified file-type
            mBuffer.AppendLiteral("201: ");

            // Names must be escaped and relative, so use the pre-calculated length
            // of the directory name as the offset into the string
            // NS_EscapeURL adds the escaped URL to the give string buffer
            NS_EscapeURL(entryName + mNameLen,
                         entryNameLen - mNameLen,
                         esc_Minimal | esc_AlwaysCopy,
                         mBuffer);

            mBuffer.Append(' ');
            mBuffer.AppendInt(ze->RealSize(), 10);
            mBuffer.Append(itemLastModTime); // starts/ends with ' '
            if (ze->IsDirectory())
                mBuffer.AppendLiteral("DIRECTORY\n");
            else
                mBuffer.AppendLiteral("FILE\n");
        }

        // Copy up to the desired amount of data to buffer
        numRead += CopyDataToBuffer(aBuffer, aCount);
    }

    *aBytesRead = numRead;
    return NS_OK;
}

uint32_t
nsJARInputStream::CopyDataToBuffer(char* &aBuffer, uint32_t &aCount)
{
    const uint32_t writeLength = std::min(aCount, mBuffer.Length() - mCurPos);

    if (writeLength > 0) {
        memcpy(aBuffer, mBuffer.get() + mCurPos, writeLength);
        mCurPos += writeLength;
        aCount  -= writeLength;
        aBuffer += writeLength;
    }

    // return number of bytes copied to the buffer so the
    // Read method can return the number of bytes copied
    return writeLength;
}